In existing vehicle control systems, by means of obtaining some parameters (e.g., sideslip angle or slip rate of the vehicle etc.) at the instantaneous time while the vehicle runs can control the vehicle more effectively. On automobiles in early stage, the running parameters were measured by means of onboard sensors; as GPS technology is widely used, the technique of utilizing GPS technology to calibrate the sensors and thereby obtaining vehicle running parameters has been proposed extensively.
U.S. Pat. No. 6,681,180 provided a method for judging whether the vehicle wheels slip by GPS on the basis of a two-wheel vehicle model; with the method, the sideslip angle of the vehicle can be obtained dynamically. Said method employs an apparatus comprising a signal collection unit and an electronic control unit; said signal collection unit comprises a GPS configured to obtain speed and position signals of the vehicle, a gyro configured to obtain angular speed signal of the vehicle, and an acceleration sensor configured to obtain acceleration signal of the vehicle; said electronic control unit comprises a data receiving module configured to obtain the data of the signal collection unit and a data processing module configured to calculate sideslip angles for the wheels of the vehicle. The data receiving module of said electronic control unit obtains speed and position signals of the vehicle from the GPS, the angular speed signal from the gyro, and the acceleration signal from the accelerometer, and the data processing module calculates the centroidal speed, the speeds of front and rear wheels in direction x and y, and the sideslip angles of front and rear wheels. With above apparatus and method, the instantaneous sideslip angle can be measured while the vehicle runs. Though the apparatus and method can partially reduce the occurrence of wheel lockup during braking while the vehicle turns, on one hand, the wheels often can't take full advantage of ground braking force and therefore the braking length is increased while the vehicle turns, on the other hand, wheel lockup still occurs often.